The purpose of this project is to (1) investigate the effect of weight loss on bone mass development in adolescent females and (2) to assess the efficacy of multi-skill training (such as stress management) in the treatment of obesity. This is a prospective clinical investigation. Over 100 obese females, Tanner stages 2-4 will be recruited to participate in the project which includes baseline, six and twelve month testing (bone mass and body composition measurements) and a six month weight loss program. The primary objectives for this study will be evaluated by comparing changes in bone mass measurements to changes in body weight using multiple regression, the Y variable being changes in bone mass and X being changes in body weight. Other potentially confounding variables, which will be analyzed in this regression equation, are calcium intake, baseline Tanner stage, activity level and height. The efficacy of multi-skill training in the treatment of obesity will be evaluated via pre/post weight loss program adiposity and anxiety measures.